This invention relates to a process for brewing, in conventional brewing plants using standard equipment and natural ingredients, a beer of reduced alcohol and calorie content, i.e., less than about 2% alcohol by weight, and having the taste, aroma, mouth feel, appearance, and foam stability of beer of higher alcohol content.
Beers of reduced alcohol content have been proposed in the patent and other literature. A number of processes are briefly surveyed in an article by M. W. Brenner entitled "Beers for the Future" published in the MBAA Technical Quarterly, Vol. 17, No. 4, 1980.
In the patent literature are noted Schimpf (U.S. Pat. No. 3,852,495) who makes a low alcohol beer by a double fermentation with removal of alcohol produced in the first fermentation before initiating the second fermentation.
Uhlmann (U.S. Pat. No. 613,915) utilizes a 170-175.degree. F. mash to favor formation of dextrins over maltose, and then evaporates alcohol after fermentation. To renew the beer flavor, kraeusen is added to the product remaining after boiling.
Nilson (U.S. Pat. No. 721,383) mashes the malt at 100.degree. F., removes the liquor containing the diastase, mixes the hot cooker mash into the remainder of the malt mash to raise the temperature of the malt mash rapidly to 176.degree. F. with added steam, and adds the liquor back to reduce the mash temperature to 162.degree. F. to produce a wort of low sugar content.
In a series of U.S. patents to Heuser U.S. Pat. Nos. 1,275,254, 1,290,191 and 1,455,397, the author shows beers of low alcohol content and condensed beers which can be diluted to drinking consistency.
There is known in the brewing art a technique of mashing known as "Springmaischverfahren" or jump-mashing, which was developed by Windisch around 1905 in Berlin. It involves a low malt mash temperature of 95-110.degree. F. and pumpover of the malt mash into water at 212.degree. F. to arrive at a conversion temperature of 169.degree. F. which is maintained with added heat. This process will produce a low alcohol beer, but there is considerable killing of alpha-amylase enzyme (over 50%) before the temperature reaches 169.degree. F. with resultant slow starch conversion, turbid wort, unacceptable beer flavor, and a real degree of fermentation (RDF) of below 40%.
Accordingly, it is a principal object of this invention to provide a method of making a completely attenuated low alcohol beer which has less than 2% alcohol by weight and a calorie content in the range of "light beers" while retaining all of the taste, aroma, foam, stability, mouth feel and appearance characteristics of conventional beer.
It is a further object to make such low alcohol beer using standard brewing equipment and all natural ingredients.
It is still a further object to provide a process for making low alcohol beer using a unique mashing technique which we call "Step mashing" in which the protein rest, and cooker mash-in temperature can be varied without adversely affecting the final product and in which the malt mash is pumped incrementally into a cooker mash which already has been cooled to the desired conversion temperature, thus instantaneously raising the temperature of each malt mash particle addition above the beta-amylase activity range while avoiding substantial heat destruction of the alpha-amylase enzymes in the malt mash. Fermentation is pursued until full attenuation (complete yeast fermentation) is reached and nowhere in the process is any alcohol removed, e.g., by vacuum distillation or reverse osmosis.
Still another object is to provide a Step mashing technique in which only water is in the cooker which is maintained at a temperature of about 169-174.degree. F. in place of a cooker mash and the main mash is pumped into the hot water to raise the temperature of the main mash addition above the beta-amylase activity range substantially instantaneously and then rapidly to the temperature of the cooker water for conversion.
These and other objects and advantages will become apparent hereinafter.